System for adjusting the fuel supply in internal-combustion engines



Dec. 23, 1952 E. sTuMP SYSTEM FOR ADJUSTING THE FUEL SUPPLY IN INTERNAL-COMBUSTION ENGINES Filed sept. 16, 1949 Patented Dec. 23, 1952 SYSTEM FOR ADJ USTIN G THE FUEL SUPPLY IN INTERNAL-COMBUSTION ENGINES Eugen Stump, Stuttgart-Unterturkheim, Germany, assignor to Daimler-Benz Aktiengesellschaft, Stuttgart-Unterturkheim, Germany Application September 16, 1949, Serial No. 116,062 In Germany October 1, 1948 Cl. 12S-98) 14 Claims. l

This invention relates to a device for the adjustment of the quantity of fuel supplied to internal combustion engines and more particularly to internal combustion engines of the injection type for motor vehicles.

It is known to stop the engine with the aid of a -rotary handle or rotary knob, Which serves simultaneously for the variable adjustment of a no-load limit position for the foot-operated fuel governing gear, by turning the rotary handle or rotary knob beyond the 11o-load position up to the complete cutting off of the fuel supply or to the stoppage of the engine. This method of stopping the machine has the drawback, however, that in order to re-start the engine the no-l-oad position has to be readjusted -again and again which requires an additional manipulation and attention and reduces the reliability and ac curacy of the adjustment. Moreover, it is relatively troublesome to turn the vrotary knob up to the stoppage of the engine.

It is the object of the present invention to avoid these disadvantages.

A special object of the present invention to ensure a permanent readiness of the engine for operation with accurately adjusted idling even after the stoppage of the engine and moreover to render possible the stopping itself in a very simple and quick manner.

With these objects in View, an important feature of the present invention consists in the provision of a device which permits adjustment of the engine to a predetermined limit load, more particularly to a predetermined quantity of fuel for idling, and moreover, to stop the engine independently of this adjustment, more particu larly by cutting on the fuel supply. Preferably, for stopping the engine, the device is provided to be operated in such a Way that on termination of the operating impulses intended to stop the engine the device will automatically return to its limiting position which has been adjusted independently thereof. To this end the device comprises a bearing member which carries the operating gear and with relation to which the gear can be adjusted for changing the no-load setting, said bearing member not being affected by said adjustment but being adjustable as a unit together with the operating gear, for stopping the engine. The variable adjustment of the idling in this case is effected advantageously by screwing a rotary knob which can be thread-ably engaged with the bearing or carrying member and connected with the lever gear so as to be non-shiftable in an axial direction, while for stopping the machine the rotary knob together with the carrying member is adjustable in an axial direction, advantageously against spring action. Both these movements can be carried out independently of each other so that the once adjusted no-load position of the device or with it (provided the other conditions remain unchanged) the once adjusted no-load speed of the engine remain unchanged, no matter how many times the device has been operated in the meantime for stopping the engine. Moreover, the push button-like operation of the device permits a particularly advantageous simplification and acceleration of the stopping operation.

In normal working order it will be suiicient in general to actuate the device for a few moments only (e. g., by depressing the knob), in order to stop the engine, while letting it go after the stopping of the engine, so that it may hereafter return automatically and immediately to its running light or idling position. However, under certain conditions, e. g. in case of a downhill journey of the vehicle, it may be desirable to leave the engine in its stopped position for a longer period without having to actuate the device permanently by hand (or the like). According to a further feature of the invention, therefore, there is provided a locking device by means of which the operating device can be retained in its position for stopping the engine. This may be achieved, e. g., in a simple manner by locking the carrying member serving for the stopping, after shifting it into its stopping position, at a fixed wall member or the like, by slight lateral swinging, against return to its running light position, e. g. by means of an annular notched surface. Advantageou-sly a lever 4provided with a stop and permitting the part of the governing gear connected with the quantity governing member to move back to the adjustable limit position defined by the device, serves to transmit the action of the device upon the fuel governing rod and lever gear, while the part of the rod and lever gear connected with the operating lever (gas pedal) may remain unhindered in its motion.

Other and further objects, features and advantages of the invention will be pointed out hereinafter and appear in the appended claims forming part of the application.

In the accompanying drawing a new preferred embodiment of the invention is shown by way of illustration 'and not by way of limitation.

In the drawing:

Fig. 1 is a general survey, in a simplified representation, showing the device with the governing gear mounted at a vehicle diesel engine,

Fig. 2 is a section through the device on a larger scale, and

Figure 3 is a view similar to that of Figure 2 with the parts in a different relative position.

The quantity of fuel supplied to the vehicle driving engine through the injection pump I is governed by a lever 2 which serves to adjust, e. g. a toothed governing rack mounted within the pump for turning the pump pistons or to effect the regulation in any other suitable manner (e. g. by adjusting the stroke of the pump piston). The lever 2 is connected, through a rod 3, with a lever 4 mounted on the shaft or pin 5. A return spring 6 which in the practical embodiment is advantageously arranged between the rod 3 and the shaft 5, tends to retract the lever 2 with the rod and lever gear system 3, 4, from the full load position V into the running light position L which is defined by a stop 1 against which the lever 4 bears and which is arranged at one end of a twoarmed lever 8 also mounted on the shaft 5. The other end of this lever is connected to a Bowden cable 9 which in the manner hereinafter described can be operated by a device II with operating knob I2 secured to the dash board IE), thereby adjusting also the stop 1.

Mounted for rotation on the shaft is moreover a further lever I3 including a stop I4 and coupled, e. g. adjustably, with a rod I5 whose opposite end is connected to the foot lever I8 (gas pedal) which is pivoted at I6 and urged upwards by a spring I1 for arbitrary adjustment of theamount of fuel. It will be understood that the spring I1 may also be arranged in the pivot I6 0r at any other point and designed in any suitable manner.

Fig. 2 shows the device I I on a larger scale. The casing of the device consists of a cap member I9 of pressed sheet metal and a bearing member 2G which is centered in an opening of the dash. board I0. Both parts are interconnected, e. g., at the flanges 2l and commonly held in an axial direction by a cap nut 22 screwed on to the bearing member 2B. Welded to the casing I9 is a U- shaped member 23 carrying the casing 24 for the Bowden cable. The casing I9 moreover possesses a non-circular, e. g. square hole 25 in which is slidably but non-rotatably guided, advantageously with a small play, a carrying member 26 which at its opposite end is mounted in the bearing member 20 in such a way that it is free to move with respect thereto in a left hand direction, but prevented from moving to the right by a spring ring 21. A spring 28 inserted between this spring ring and the left hand wall of the cap member I9 forces the carrying member in a right hand direction into engagement of the spring ring 21 with the bearing member 2i?. The carrying member has an annular notch or turned off portion 29 serving as a locking notch in a way which will be hereinafter described.

The operating knob (rotary knob) I2 is moreover coupled, so as to be rotatable but relatively non-slidable on the one hand, by means of a thread 30, with the carrying member 26 and on the other hand, by means of a spring ring 3l or the like, with the cylindrical part 32 of 4a slide 33 which is of square shape and axially slidable in a square hole disposed in a collar 34 of the carrying member 26, the end 9 of the Bowden cable being secured to the slide 33.

The device according to the invention operates ais follows:

In the drawing the device is shown in the running light position corresponding to the position L of the lever 2. The lever 4 bears against the stop 1 while a play e is existing between the lever 4 and the stop I Therefore, when depressing the pedal I3, the lever 2 can play only between V and L. By turning the knob I2, the slide 33 and with it the Bowden cable 9 can be axially moved, whereby the lever S or the stop 1 is adjusted to the one or the other side and accordingly the no-load limit position L is more or less changed. The carrying member 26 remains immovable in its position. Now, if it is intended to stop the engine, the knob I2 is pressed to the left in an axial direction, whereby the knob I2, the carrying member 26 and the slide 33 are moved as a unit against action of the spring 28 and the lever 8 is swung in the direction by such an amount that the lever 2 under action of the spring 6 which causes the lever 4 to follow the stop 1, moves to the zero position Il, thus stopping the engine. In order to keep the device in the stopped position it is sufficient to exert a light pressure, transversely to the axial direction, upon the knob l2, after the same, or the carrying member 26, has been moved into the extreme left hand position; the locking notch 29 thereby engages behind the left hand front face of the bearing member 2B (whereby the carrying member 26 swings slightly about the interior edge of the opening 25) and thus locks the device under the pressure of the spring 28. By a slight oppositely directed transverse pressure the notch 29 is again disengaged from its position behind the wall of the bearing member 20 so that the spring 28 causes the device to bound back into the originally adjusted running light position, as shown in the drawing. If, in the normal case, there has been no previous locking by the notch 29, the device will automatically return to the adjusted running light position as the pressure exerted on knob I2 decreases.

It will be understood that the invention is not restricted to the embodiment as illustrated. Instead of locking the parts by the notch 28 it is also possible to provide movable automatic locking members or e. g. members which are to be operated separately. By way of alternative, rod and lever systems may be provided instead of the Bowden cable for operating the device. Moreover, the stop 1 for adjustment of the noload position may be arranged in any other manner, e. g., as a transversely slidable stop or the like. Furthermore, a similar governing system or method may be provided, e. g., for carburetor engines or the like.

What I claim is:

l. A. system for controlling and interrupting the operation of an internal combustion engine comprising control means for controlling the supply of fuel to the engine, means inuencing said control means for selectively adjusting the supply of fuel 1n correspondence with the desired operating conditions of the engine, a device influencing the control means for adjusting the supply lof fuel at a minimum value and a device also, in-

fluencing the control means for temporarily in-y terrupting the supply of fuel, both said devices being so interconnnected that the first device can be made inoperative or operative by the second device without change in the adjustment thereof.

2. A system for controlling and interrupting the operation of an internal combustion engine comprising control means for controlling the supply of fuel to the engine, means inuencing said control means for selectively adjusting the supply of fuel in correspondence with the desired working conditions of the engine, a. device influencing the control means for adjusting the supply of iiuid to no-load conditions and a second device also inuencing the control means for temporarily interrupting the supply of fuel, both said devices being so interconnected that the rst said device may be actuated by the second said device from and operative position to an inoperative position and back to an operative position without altering the adjustment.

3. A system as in claim 2 further comprising a common actuating member and a common actuating link for both said devices.

4. A system for controlling an internal combustion engine comprising control means for adjusting the fuel supply, further means influencing said control means for selectively adjusting the fuel supply in correspondence with the desired working conditions of the engine, additional means influencing said control means and comprising an adjustable carrying member, an actuating member supported by the adjustable carrying member and including means for adjustably positioning the actuating member relatively to the carrying member, and transmission means connecting the actuating member to the control means for transmitting to the control means selectively either the relative movement of the actuating member alone or the movement of the carrying member and of the actuating member.

5. A system according to claim 4 wherein the means for selectively adjusting the fuel supply and the additional means each further comprise an abutment member engageable with clearance with the control means.

6. A system for controlling an internal combustion engine comprising control means for controlling the fuel supply to the engine, means influencing said control means for selectively adjusting the fuel supply, an abutment member engageable with the control means to limit downward selective adjustment of the fuel supply, a connecting rod for adjusting the position of the abutment member, an actuating member for the connecting rod, a movable carrying member supporting the actuating member whereby the actuating member is movable either relatively to or with the carrying member in such a manner that relative movement cf the actuating member will transmit movement to the abutment member within an idling range of the engine and that the joint movement of the carrying member and actuating member will displace the abutment member to interrupt the fuel supply.

7. A system according to claim 6 wherein the actuating member is threadably engaged in the carrying member and the carrying member and actuating member are movable together along a common axis.

8. A system according to claim 6 wherein the actuating member is threadably engaged in the carrying member and wherein the carrying member and actuating member are movable together along a common axis, in combination with spring means urging the actuating member relatively to the carrying member into a position corresponding to no-load operation.

9. A system according to claim 6 wherein said connecting rod comprises a transmission member rotatable with the actuating member, said transmission member being axially ixed relatively to said actuating member, the combination further comprising a relatively iixed part whereby the carrying member is held against rotation and free for axial movement in said fixed part, spring means being interposed between said carrying member and nxed part.

10. A system according to claim 6 wherein the actuating member comprises an actuating button.

l1. A system for controlling and interrupting the operation of an internal combustion engine comprising a fuel adjustment device, a relatively xed housing member, a carrying member 1ocated in and movable relatively to the housing member, the carrying member being spring urged into an end position and slideable against the spring action, an actuating member adjustably positioned by threaded engagement in the carrying member, an element coupled with the actuating member, an abutment member connected with ysaid element, said abutment member being so engageable with said fuel adjustment device that screw adjustment of the actuating member will adjust said actuating member relatively to the carrying member thereby setting the fuel adjustment device to a predetermined minimum supply and that sliding of the carrying member against spring action will adjust said carrying member together with said actuating member and element as a unit thereby enabling interruption of the fuel sup-ply.

12. A system according to claim 11 comprising means for locking the carrying member in an adjusted position against such spring action.

13. A system according to claim 11 wherein the carrying member is laterally displaceable in combination with complementarily engageable parts on an edge of the carrying member and on the housing member whereby the carrying member may be locked in adjusted position against said spring action by engagement of said parts.

14. A system for controlling and interrupting the operation of an internal combustion engine comprising a control rod for controlling the fuel supply, an element for actuating the control rod, a clearance being provided between the element and the control rod, an abutment member for limiting the movement of the control rod within the said clearance and a device for adjusting the position of the abutment member comprising a relatively fixed part, an actuating member engageable with the abutment member and an adjustable carrying member for said actuating member, means for displacing the actuating member relatively to the carrying member, abutment means for the carrying member on the relatively iixed part, spring means urging the carrying member against said abutment means and against which the carrying member and actuating member may be manually displaced toward the relatively xed part, in such manner that, upon release of said actuating member, said spring means will return said actuating and carrying members and said abutment member to original adjusted position.

EUGEN STUMP.

REFERENCES CITED The following references are of record in the 

